1. Field of the Invention
This invention relates to a shampoo composition and more particularly, to a shampoo composition which comprises a shampoo base containing anionic surface active agents and decomposition derivatives of keratin material and which shows an excellent hair conditioning effect and mild eye irritation.
2. Description of the Prior Art
Hitherto employed shampoos generally comprise singly or in combination, as their base, anionic surface active agents such as alkylsulfates and polyoxyethylenealkylsulfates and the like, nonionic surface active agents such as polyoxyethylene alkyl ethers, fatty acid alkylolamides and the like, or amphoteric surface active agents such as alkylbetaines, alkylamine oxides and the like.
On washing of hair with the shampoos containing these bases, it will be found that the sebum or other oils existing on the hair surface are washed off too much, so that the feeling of the washed hair becomes very poor to the touch and hard to comb or brush. In addition, when completely dried, such hair is hard to style. Especially in winter season of low humidity, since static electricity is ready to generate on brushing, there occurs a phenomenon such as of hair fly with the attendant disadvantage that the hair is hard to comb, causing split-ends or broken hairs.
In order to overcome the above disadvantage, there is known a method of adding oils to ordinary shampoo bases to supplement the oil at the time of washing. Ordinarily employed shampoos are admixed with a variety of oils.
However, in the formulation system of shampoo, the system is in an emulsified or solubilized state by the action of surface active agents, so that it is difficult to add oils in amounts sufficient for scalp and hair without impairing the stability of the system.
With shampoos to which large amounts of oil are added, an amount of adsorption of oil on hair increases but they involve disadvantages that lathering and detergency which shampoos should orginally have deteriorate extremely with the commercial value being considerably impaired.
In recent years, on the other hand, there have been proposed many shampoo compositions including cationic polymers for the purpose of imparting a rinsing effect to hair after washing. However, these compositions have the following disadvantaages: (1) Showing a conditioning effect but deteriorated in lathering ability and detergency; (2) Colored or discolored as time goes; (3) Excellent in lathering characteristics but poor in conditioning effect; and (4) High in cost.